{{short description|German medical researcher (born 1967)}} {{Infobox scientist | name = Michael Ristow | image = | image_size = | caption = | birth_date = {{Birth date and age|1967|4|24}} | birth_place = [[Lübeck]], [[Germany]] | death_date = | death_place = | citizenship = | ethnicity = | field = [[Biochemistry]], [[Medicine]] | work_institutions = [[Charité]], Berlin, Germany <br/> [[ETH Zurich]], Switzerland <br/> [[University of Jena]], Germany <br/> [[Harvard University]], Cambridge <br/> [[Joslin Diabetes Center]], Boston <br/> [[University of Cologne]], Germany | alma_mater = [[Ruhr University]] Bochum, Germany | doctoral_advisor = | doctoral_students = | known_for = [[hormesis#Mitohormesis|mitohormesis]], [[antioxidant]], [[mitochondria]]l [[metabolism]], [[aging]], [[nutrition]] | author_abbrev_bot = | author_abbrev_zoo = | influences = | influenced = | prizes = | religion = | footnotes = | signature = }}
'''Michael Ristow''' (b April 24, 1967) is a German [[medical research]]er who has published influential articles on [[biochemistry|biochemical]] aspects of [[mitochondria]]l [[metabolism]] and particularly the possibly health-promoting role of [[reactive oxygen species]] in diseases like type 2 diabetes, obesity and cancer, as well as general [[aging]] due to a process called [[hormesis#Mitohormesis|mitohormesis]].
Ristow was born in [[Lübeck]] in the North of [[Germany]]. He graduated at the [[University of Bochum]] in 1992 and received his M.D. from [[University of Bochum]] in 1996. He was appointed to the [[University of Jena]] in 2005 as a full [[professor]] in [[nutritional science]], as a full [[professor]] in [[energy metabolism]] at the [[ETH Zurich]] in 2013, and a full [[professor]] in Experimental [[Endocrinology]] and [[Diabetology]] at [[Charité]] Berlin in 2023, also as the director of the Institute of Experimental Endocrinology.<ref>[https://www.charite.de/en/service/press_reports/artikel/detail/metabolism_expert_joins_charite_to_advance_understanding_of_age_related_diseases New institution's announcement of Ristow joining]</ref>
In 2007, Ristow’s group published evidence which could explain the basis of the observed extension of lifespan by restriction of sugar intake. In experiments on a model organism, the worm [[Caenorhabditis elegans]], they found that lowering the availability of [[glucose]] extended the lifespan of the worms. It has been known since the 1930s that restricting calories while maintaining adequate amounts of other nutrients extends lifespan across a broad range of organisms. The mechanism has been proposed as a change in the activity of the [[sirtuins]]. Michael Ristow shows in his article that this effect can also occur independent of sirtuins, since worms deficient for sirtuins still show extended life span in states of sugar restriction.<ref name = glucose_restriction>{{cite journal |vauthors=Schulz TJ, Zarse K, Voigt A, Urban N, Birringer M, Ristow M |title=Glucose restriction extends Caenorhabditis elegans life span by inducing mitochondrial respiration and increasing oxidative stress |journal= Cell Metabolism|volume=6 |issue=4 |pages=280–93 |year=2007 |pmid=17908557 |doi=10.1016/j.cmet.2007.08.011|doi-access=free }}</ref><ref>[https://www.reuters.com/article/healthNews/idUSL0244996420071002 "Reuters" article on Ristow’s findings on the positive role of oxidative stress]</ref><ref>[http://www.eurekalert.org/pub_releases/2007-10/cp-asm092607.php "Eurekalert" article on Ristow’s findings on the positive role of oxidative stress]</ref>
Most importantly, Ristow's research suggests that this is a [[hormesis#Mitochondria|mitohormetic]] effect, as reviewed in.<ref>{{cite journal |author1=Michael Ristow |author2=Sebastian Schmeisser |title=Extending lifespan by increasing oxidative stress |journal=Free Radical Biology and Medicine |volume=51 |issue=2 |pages=327–336 |year=2011 |pmid=21619928 |doi=10.1016/j.freeradbiomed.2011.05.010|doi-access=free }}</ref> [[Hormesis]] is a controversial concept in which it has been demonstrated that the induction of low-level stress can promote health and lengthen lifespan in some species, while higher levels of the same stress exert detrimental effects. Ristow's interpretation was that in response to a decrease in [[glycolysis|glycolytic]] energy production, the worms have to generate [[Adenosine triphosphate|ATP]] by [[oxidative phosphorylation]] in the mitochondria, leading to increased production of [[reactive oxygen species]]. Due to a vaccination-like response, the organism produces more defenses against [[oxidative stress]], including increased activity of [[catalase]]. Supplementation with [[antioxidants]] abolishes the increase in lifespan, and so does disruption of an [[AMP-activated protein kinase|AMP-kinase]] but not disruption of [[sirtuins]].<ref name = glucose_restriction/>
In a follow-up study that experienced significant media attention,<ref>[https://www.nytimes.com/2009/05/12/health/research/12exer.html?ref=research Antioxidants & exercise: New York Times]</ref><ref>[http://news.bbc.co.uk/2/hi/health/8043456.stm Antioxidants & exercise: BBC]</ref><ref>[http://www.scientificamerican.com/podcast/episode.cfm?id=vitamins-block-some-exercise-benefi-09-05-12 Antioxidants & exercise: Scientific American]</ref> Ristow and colleagues have shown that supplementing humans with antioxidants during physical exercise blocks the health-promoting effects of exercise, suggesting that free radicals produced during exercise are responsible and required for the effects of exercise.<ref>{{cite journal |author=Michael Ristow, Kim Zarse, ... ,Matthias Blüher |title=Antioxidants prevent health-promoting effects of physical exercise in humans |journal=Proc. Natl. Acad. Sci. U.S.A. |volume=106 |issue=5 |pages=8865–8870 |year=2009 |pmid=19433800 |doi=10.1073/pnas.0903485106 |pmc=2680430|bibcode=2009PNAS..106.8665R |doi-access=free }}</ref>
These findings bring into question [[Denham Harman]]'s [[free radical theory]] of [[aging]], and provide a mechanistic basis to question the application of [[antioxidants]] to human health.<ref>{{cite journal |vauthors=Bjelakovic G, Nikolova D, Gluud LL, Simonetti RG, Gluud C |title=Mortality in randomized trials of antioxidant supplements for primary and secondary prevention: systematic review and meta-analysis |journal=JAMA |volume=297 |issue=8 |pages=842–57 |year=2007 |pmid=17327526 |doi=10.1001/jama.297.8.842}}</ref><ref>{{cite journal |vauthors=Ristow M |title=Unraveling the truth about antioxidants: mitohormesis explains ROS-induced health benefits |journal=Nature Medicine |volume=20 |issue=7 |pages=709–11 |year=2014 |pmid=24999941 |doi=10.1038/nm.3624|s2cid=32448892 }}</ref><ref>{{Cite journal | last1 = Ristow | first1 = M. . | last2 = Zarse | first2 = K. . | title = How increased oxidative stress promotes longevity and metabolic health: the concept of mitochondrial hormesis (mitohormesis) | journal = Experimental Gerontology | volume = 45 | issue = 6 | pages = 410–418 | year = 2010 | pmid = 20350594 | doi = 10.1016/j.exger.2010.03.014 | s2cid = 207727334 }}</ref>
Subsequently Ristow demonstrated that the widely used supplement [[glucosamine]] promotes longevity of ''Caenorhabditis elegans'' and elderly mice.<ref>{{cite journal | author = Weimer S | display-authors = etal | year = 2013 | title = D-Glucosamine supplementation extends life span of nematodes and of ageing mice | journal = [[Nature Communications]] | volume = 8 | page = 3563 | pmid = 24714520 | doi = 10.1038/ncomms4563 | pmc = 3988823 }}</ref> Independently, it was shown that regular intake of glucosamine is associated with a remarkable reduction in mortality in humans, suggesting that glucosamine supplementation may be useful to promote human healthspan.<ref>{{cite journal | author = Bell G. A. | display-authors = etal | year = 2012 | title = Use of glucosamine and chondroitin in relation to mortality | journal = European Journal of Epidemiology| volume = 27 | issue = 8| pages = 593–603 | pmid = 22828954 | doi = 10.1007/s10654-012-9714-6 | pmc = 3557824 }}</ref>
In earlier years, Ristow published a seminal article describing a genetic mutation associated with extreme human obesity.<ref>{{cite journal | title =Obesity Associated with a Mutation in a Genetic Regulator of Adipocyte Differentiation | journal =The New England Journal of Medicine | volume =339 | issue =14 | pages =953–959 | date =October 1, 1998 | pmid = 9753710 | doi =10.1056/NEJM199810013391403 | last1 =Ristow | first1 =Michael | last2 =Müller-Wieland | first2 =Dirk | last3 =Pfeiffer | first3 =Andreas | last4 =Krone | first4 =Wilhelm | last5 =Kahn | first5 =C. Ronald | doi-access =free }}</ref>
Ristow’s laboratory has provided direct evidence supporting the so-called [[Warburg hypothesis]]. Specifically Ristow has shown that forced metabolic activity and [[Respiration (physiology)|respiration]] of [[mitochondria]] efficiently blocks cancer growth<ref>{{cite journal |author1=Tim J. Schulz |author2=Rene Thierbach |author3=Anja Voigt |author4=Gunnar Drewes |author5=Brun Mietzner |author6=Pablo Steinberg |author7=Andreas F. H. Pfeiffer |author8=Michael Ristow | title =Induction of Oxidative Metabolism by Mitochondrial Frataxin Inhibits Cancer Growth: Otto Warburg Revisited | journal =The Journal of Biological Chemistry | volume =281 | issue =2 | pages =977–981 | year =2006 | url =http://www.jbc.org/cgi/reprint/281/2/977.pdf | pmid = 16263703 | doi =10.1074/jbc.M511064200 |s2cid=31545439 |doi-access=free}}</ref><ref>{{cite journal |author1=Gergor Beuster, Kim Zarse |author2=Michael Ristow |name-list-style=amp | title =Inhibition of alanine aminotransferase in silico and in vivo promotes mitochondrial metabolism to impair malignant growth | journal =Journal of Biological Chemistry | volume =286 | issue =25 | pages =22323–30 | year =2011 | pmid = 21540181 | doi=10.1074/jbc.M110.205229 | pmc=3121379 |doi-access=free }}</ref> as anticipated by [[Otto Heinrich Warburg]] as early as in 1924.
Independent of his work on oxidative stress, Ristow has recently shown that increased concentrations of the [[trace metal]] [[Lithium]] contained in drinking water are associated with increased lifespan in Japan suggesting a readily available [[anti-aging]] intervention.<ref>{{cite journal |author=Kim Zarse, ... , Michael Ristow|title=Low-dose lithium uptake promotes longevity in humans and metazoans |journal=Eur J Nutr |volume=50 |issue=5 |pages=387–389 |year=2011 |pmid=21301855 |doi=10.1007/s00394-011-0171-x |pmc=3151375}}</ref>
==See also== *[[Aging]] *[[Antioxidant]] *[[Hormesis#Mitochondria|Mitochondrial hormesis]]
==References== <references/>
==External links== *[https://expendo.charite.de/en/ Homepage of the Institute for Experimental Endocrinology] *[https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=ristow+m Complete list of Ristow's scientific publications at PubMed] *[https://scholar.google.de/citations?user=HkSI1LoAAAAJ&hl=en GoogleScholar profile] *[http://www.researcherid.com/rid/O-9858-2014 ResearcherID profile] *[https://orcid.org/0000-0003-2109-2453 ORCID profile] *[https://twitter.com/Prof_M_Ristow Twitter profile]
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{{DEFAULTSORT:Ristow, Michael}} [[Category:1967 births]] [[Category:German medical researchers]] [[Category:Living people]] [[Category:Ruhr University Bochum alumni]] [[Category:Academic staff of ETH Zurich]] [[Category:Academic staff of the University of Jena]] [[Category:Harvard University faculty]] [[Category:Academic staff of the University of Cologne]] [[Category:Scientists from Lübeck]]